Quantitation of meloxicam in the plasma of koalas (Phascolarctos cinereus) by improved high performance liquid chromatography

摘要: An improved method to determine meloxicam (MEL) concentrations in koala plasma using reversed phase high performance liquid chromatography equipped with a photo diode array detector was developed and validated. A sample clean-up step carried out hydrophilic- lipophilic copolymer solid extraction cartridges. MEL separated from an endogenous interference isocratic mobile [acetonitrile 50 mM potassium phosphate buffer (pH 2.15), 45 : 55 (v v)] on Nova-Pak C18 4-µm (300 × 3.9 mm) column. Retention times for piroxicam were 8.03 5.56 min, respectively. Peak area ratios of the internal standard (IS) used regression analysis calibration curve, which linear 10 1,000 ng/mL (r(2) > 0.9998). Average absolute recovery rates 91% 96% IS, This had sufficient sensitivity (lower quantitation limit ng/mL), precision, accuracy, selectivity routine 250-µL volumes. Our technique clearly resolved peak complex matrix accurately measured small